股東可扣抵稅額減半自民國104起實施，本國個人股東獲配股利時，可扣抵綜所稅的稅額減少一半，造成投資人獲配股利所得的實質稅負增加，又104起綜合所得稅最高稅率調升至45%，投資人是否會基於稅賦上的考量而有棄權息的狀況，本研究在討探討是否股東可扣抵稅額減半是否有股利顧客效果的存在。
本研究使用t檢定及迴歸模型分析，探討股東可扣抵稅額減半對除權息日前後累積異常報酬率之影響，研究區間為減半前一年(103年)及當年度(104年)，對象為國內上市公司，實證結果發現實施減半當年度除權息前無棄權息的現象，但息後有回補的情況。接著又採用迴歸的方法探討本國個人股東持股比率越高的樣本，其棄權息及回補的現象是否越明顯以佐證股利顧客效果的存在。實證結果發現在減半後，本國個人股東持股比率越高的樣本，其息前棄息及息後回補的現象越明顯。

The imputed tax credit of shareholders has been halved since 2015, which implies that when individual shareholders in Taiwan receive dividends, the amount of imputed tax credit that can be used against their individual income tax has been reduced by half. This has led to an increase in the effective tax burden on investors as regards their income arising from dividends. Furthermore, given that the maximum individual income tax rate has been increased to 45% since 2015, investors might opt for dividend abstention due to tax considerations. Therefore, this study focused on whether the halving of the imputed tax credit for shareholders caused the dividend clientele effect.
This study employed t-tests and regression models for analysis and discussed the effect of halving the imputation tax credit on the cumulative abnormal returns around the ex-right/dividend date. The research period was the year before the imputed tax credit was halved (2014) and the year it was implemented (2015). The research subjects were listed companies in Taiwan. Empirical results showed that dividend abstention did not occur until the ex-right/dividend date in the year the imputed tax credit was halved, but recovered after the allotment of dividends. Subsequently, this study further explored data on individual shareholders with a high shareholding ratio and adopted a regression model to investigate whether their dividend abstention and recovery is convincing evidence of the existence of the dividend clientele effect. The results show that after the imputed tax credit was halved, these individuals showed more obvious dividend abstention before, and recovery after, the payment of dividends.

國內文獻
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